Fluoride is the most important ingredient to look for when choosing toothpaste. Fluoride is a naturally occurring mineral. Its use has been instrumental in the dramatic drop in tooth decay and cavity occurrence that has taken place over the past 50 years.

Toothpaste is available in paste, gel, or powder form. Despite the many types of toothpaste, there are some ingredients common to most varieties. These include: Abrasive agents. Scratchy materials, including calcium carbonate and silicates. These help remove food, bacteria, and some stains from your teeth.

Flavoring. Artificial sweeteners, including saccharin, are often added to toothpaste to make them taste better. While many people equate the flavor of toothpaste with mint, toothpaste is available in a variety of flavors, including cinnamon, lemon-lime, and even bubblegum (for kids -- or kids at heart).

Humectants for moisture retention. Paste and gel formulations often contain substances like glycerol to prevent the toothpaste from drying out.

Thickeners. Agents that add thickness to the toothpaste, including gums and gooey molecules found in some seaweeds, help achieve and maintain proper toothpaste texture.

Detergents. Those suds you see when you brush your teeth are from detergents like sodium lauryl sulfate.